WA braces for Narelle’s revival as cyclone tracks ‘very unusual’ path towards Perth

Western Australia is bracing for impact from Tropical Cyclone Narelle as it redevelops off the coast, with predictions Perth could be in the firing line over the weekend.

It is the first time since 2005 that a cyclone has impacted all three tropical states and territories in one swoop – the NT, Queensland and WA – according to the Bureau of Meteorology, and could also make history as the first to continue further south and cause significant impacts in Perth.

Senior meteorologist Angus Hines said there was not another cyclone that was comparable.

There have been 15 tropical cyclones to cause some impact on Perth in the past 100 years, Hines said, or one every 6.6 years, but not as severely as Narelle might if it follows one of two predicted paths.

The cyclone could also turn back inland earlier, and hit the Mid West coastal towns of Geraldton or Kalbarri instead of Perth.

“It is unique as a weather system … Tropical Cyclone Ingrid was the last time a similar path was created more than 20 years ago, but it reached the Kimberley and did not travel much further down,” he said.

“It would be very unusual if this system were to come down as far as Perth.

“Tropical Cyclone Narelle is the tenth this season across Australia, which is bang on average but its impact further south shows it is stronger than usual.”

Favourable weather conditions have contributed to the distance covered, including warm waters and a lack of wind shear which is often what slows cyclones down.

Hines said while there was not yet enough research to ascertain whether global warming was causing longer-lasting cyclones, or would into the future, it was a possibility.

“We also think we will see a change in weather patterns as a result of warmer temperatures, where there will be fewer cyclones, but they will be a higher category and cause a greater impact when they do occur,” he said.

“It will be a gradual change that occurs over a number of decades.”

The cyclone started its journey last week, developing across the Coral Sea as a category 5 and made landfall in far north Queensland as a category 4, before continuing its journey towards the NT and wreaking havoc.

Vulnerable communities including Katherine, which had recently flooded, were hit with another deluge of water despite the cyclone dropping to a tropical low as it crossed over.

The Kimberley was also hit by stormy conditions created by that tropical low, with 165 millimetres of rain falling over the past couple of days.

Across Tuesday night and Wednesday morning, the system is expected to re-intensify back into a tropical cyclone off the coast of Broome.

It is possible it will build back to a category 4 system, causing gale force winds and large waves along the Pilbara coast on Thursday, before dropping back to a category 3 as it passes Carnarvon.

Hines said the worst of the weather was expected on Sunday for Perth, with up to 100 millimetres of rain predicted between Geraldton and Perth.

It is possible that Esperance and Albany will also see some rain if the storm does continue its path down the coast.

“It has been through an array of intensities throughout its unusual lifespan,” Hines said.

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